Being a formal and general as well as the most widely accepted approach to practical rationality, rational decision theory should be crucial for justifying rational morals. In particular, acting morally should also be rational in decision theoretic terms. After defending this thesis, in the critical part of the paper two strategies to develop morals following this insight are criticized: game theoretical ethics of cooperation and ethical intuitionism. The central structural objections to ethics of cooperation are that they too directly aim (...) at the rationality of moral action and that they to do not encompass moral values or a moral desirability function. The constructive half of the paper takes up these criticisms by developing a two-part strategy to bring rationality and morals in line. The first part is to define ‘moral desirability’. This is done, using multi-attribute utility theory, by equating several adequate components of an individual’s comprehensive utility function with the moral desirability function. The second part is to introduce mechanisms, institutions, in particular socially valid moral norms, that provide further motivation for acting in accordance with morals. (shrink)

In this book some options concerning the greenhouse effect are assessed from a welfarist point of view: business as usual, stabilization of greenhouse gas emissions and reduction by 25% and by 60%. Up to today only economic analyses of such options are available, which monetize welfare losses. Because this is found to be wanting from a moral point of view, the present study welfarizes (among others) monetary losses on the basis of a hedonistic utilitarianism and other, justice incorporating, welfare ethics. (...) For these welfarist evaluations information about the social consequences of the four options are collected from the literature and eventually corrected; then the consequences for individual well-being are assessed based on psychological research about well-being dependent on the social situation of the individual; finally the aggregation formulas of the respective welfare ethics are applied to these data. Assessments by other types of ethics, e.g. Kantian ethic, are included. The strongest abatement option is found to be optimum with great unanimity. - In addition a cost-welfare analysis of greenhouse gas abatement is undertaken revealing efficient cost-welfare ratios for these measures and the most efficient ratio for the strongest option. - A final, more theoretical part discusses the moral obligations following from such evaluations. The notion of 'moral obligation' is explained in a way that, apart from moral goodness of the required act, reinforcement by formal or informal sanctions is another necessary condition for moral obligations. This leads to a conception of a historical morality according to which the demands of morality rise in the long run. Applying this conception to the greenhouse effect implies that presently we have the moral duty to raise the standards of greenhouse gas abatement as much as is politically feasible. (shrink)

The article develops a general theory of the goals of free moral commitment. The theoretical hook is the discussion of the strict efficiency striving as demanded by the movement and theory of effective altruism. A detailed example shows prima facie counterintuitive consequences of this efficiency striving, the analysis of which reveals various problems such as: merely point-like but not structural commitment; radical universalism; violation of established moral standards and institutions. The article takes these problems as an occasion to develop a (...) general theory of moral investment with moral guidelines and planning instruments of its implementation such as: efficiency; preservation of existing moral standards and obligations, especially also towards those close to one; rooted universalism with adequate consideration of all beneficiaries of one's moral concern through allocation of separate budgets; real efficiency also through inclusion of strategic and organic investments. (shrink)